PRODUCTS – When any of the following lines is defined, the player will not be able to manufacture products of the specified product classes:
Product=<product class> (e.g. “Product=Beverage” )
Product=<product class>
.
.

If you only want to allow the player to manufacture a single product class, while disabling the remaining ones, you may write the script in the following way:
[LOCKS]
Product=All

[UNLOCKS]
Product=Apparel

In this case, the game will first disable all product classes in the [LOCKS] section, and subsequently enable the Apparel product class in the [UNLOCKS] section.

CITIES – Locking cities out from player access
It is possible to lock a city as well. When a city is locked, the player will not be able to build any business in the city until the city is unlocked.
Locked cities should be defined in the City section of a script file, click here for details.

Here is a screenshot of a script modified game where the only types of firms that the player can build are retail stores and factories:

The following script hides the Corporate Details report from the Information Center and make it impossible for the player to build a TV Station. The player is also prevented from manufacturing automobile and furniture.